Pump lubrication means



Sept. 1, 1959 Filed Aug. 28, 195'? R. H. MALCOLM 2,902,012

PUMP LUBRICATION MEANS 3 Sheets-Sheet l 1522/5223071' 0 "w14 @Maleo/m Sept 1, 1959 R. H. MALCOLM 2,902,012

PUMP LUBRICATION MEANS v Filed Aug. 28, 1957 3 Sheets-Sheet 2 O I 252 WW2 i071' oerz Malcolm Sept. 1 1959 R. H. MALCOLM PUMP LUBRICATION MEANS Filed Aug. 28, 1957 3 Sheets-Sheet 3 252 a/gn for' rf d/QZCOZWZ United States Patent O PUMP LUBRICATION MEANS Robert H. Malcolm, Fort Wayne, Ind., assignor to International Harvester Company, Chicago, lll., a corporation of New Jersey Application August 28, 1957, Serial No. 680,755

,13 Claims. (Cl. 12S-41.86)

This invention relates to air pumps used to operate various internal combustion engine accessories, and more particularly to the novel means for lubricating the pump from the engine lubricating system.

The principal object of the present invention is the provision of a simple, ecient and economical means for lubricating an air pump from the lubricating system of the internal combustion engine utilized for driving the same without the need of unduly modifying the engine structure.

A further object is to provide a rotary type air pump supported on the exterior of the engine housing and novel means for supplying the air pump with lubricant.

A still further object is to provide means for supplying lubricating oil to an engine-driven air pump from the pressure lubricating system of the engine whereby the quantity of oil received by the pump for lubricating the moving parts thereof and for sealing the pressure side of the pump from the suction side is accurately controlled.

An important object is to direct and control the lubricating oil supply to an engine-driven air pump whereby a controlled quantity of lubricating oil is introduced at the periphery as well as at the center of the pump rotor and the amount is sufficient to maintain the desired seal between the pump housing and pump rotor and to properly lubricate the moving parts of the pump rotor without materially decreasing the air displacement capacity of the pump.

The foregoing and other important objects and desirable features inherent in and encompassed by the invention together with many of the purposes and uses thereof, will become readily apparent from a reading of the ensuing description in conjunction with the annexed drawings, in which:

Figure 1 is a fragmentary vertical sectional view taken longitudinally of an internal combustion engine;

Figure 2 is a sectional lView taken substantially along line 2 2 of Figure l;

Figure 3 is a fragmentary sectional view taken substantially along line 3 3 of Figure 2;

Figure 4 is a fragmentary end view of the detachable cover;

Figure 5 is a sectional view of the air pump taken substantially along line 5--5 of Figure 1; and

Figure 6 is a sectional view taken substantially along line 6-6 of Figure l. f

Referring to the drawings in detail, wherein like referance characters designate like elements throughout the various views, there is shown a fragment of an internal combustion engine block having an end wall 10 in which a bearing is secured for journalling one end of a crankshaft 11. The wall 10 also carries a bearing 12 in which is journalled one end of a cam shaft 13, as shown in Figure 1. Keyed to the crankshaft 11 externally of the w'all 10 is a gear 14 which meshes with a relatively larger gear 15 .keyed to the cam shaft 13. The gears 14 and15 constitute the engine timing gears. A detachable'icover' 16,

ice

enclosing the timing gears 14 and 15, is fastened to the end wall 10 of the engine block.

The crankshaft bearing has an annular groove 17 formed therein which, in any appropriate manner, is supplied with lubricating oil from the engine crankcase oil sump (not shown) under pressure, by means of the usual oil pump mechanism (not shown) provided for that purpose. A similar annular groove 18 is provided in the cam shaft bearing 12 and the grooves 17 and 18 are in uid communication by means of a passageway 19. An upwardly inclined passageway 20 formed in the wall 10 leads from the bearing groove 18 to the space between the wall 10 and the cover 16. From the foregoing it will be appreciated that oil under pressure is discharged to the upper part of the space enclosed by the detachable cover 16 and the end wall 10 of the engine block from the end of inclined passageway 20. It is to be understood that other means could be employed to discharge oil under pressure from the passageway 20 rather than grooves 17 and 18 and passageway 19 without departing from the spirit and scope of the invention. Furthermore, the oil could be emitted from the passageway 20 in a series of intermittent squirts rather than as a continuous ow of oil. It will be noted that the toothed rim 21 of the timing gear 15 is supported on the hub portion 22 thereof by means of a plurality of circumferentially spaced spokes 23 such that a portion of the lubricating oil being discharged from the passageway 20 passes through the space between the spokes `23 and impinges upon the upper portion of the interior surface of the detachable cover `16. The lubricating oil discharged from the passageway 20 not only lubricates the timing gears 14 and 15 but also is utilized to lubricate and seal the air pump designated generally by numeral 24 in a manner as will be pointed out hereinafter.

The extreme end of the cam shaft 13 is provided with an axially extending threaded recess 25 for threadingly receiving the shank portion 26 of an adapter element 27. A thrust washer 28 is interposed between the enlarged head 29 of the adapter element 27 and the hub portion 22 of the timing gear 15 such that when the shank 26 of the adapter element 27 is threaded into the recess 25, the timing gear 15 is securely fixed to the cam shaft 13. As shown in Figure l, a hexagonally-shaped axially opening recess 30 is provided in the enlarged head portion 29 for a purpose which will be pointed out hereinafter.

The detachable timing gear cover 16 enclosing the timing gears 14 and 15 is provided with an opening 31 coaxial with the cam shaft 13. Circling the opening 31 on the exterior of the cover 16 is a raised annular boss 32 which serves as an accessory attachment pad.

Although a specific illustration of a form of air pump 24 to be attached to the engine is to be described heremafter, it is to be understood that any rotary-type pump capable of operating in a like manner for delivering air or liquid under pressure could be used in lieu thereof without departing from the spirit and scope of the invention. Likewise, the fact that the particular pump 24 shown and to be described is used to deliver air under pressure to the engine crankcase to ventilate the same, such use is not to be construed as limiting the application of the invention solely to that use. The pump 24 ncludes a casing or housing 33, which, in turn, comprises a cylindrical section 34 and an integrally formed end wall 35. The end of the section 34 opposite the wall 35 is provided with a plurality of circumferentially spaced tabs 36 against which the peripheral edge of an end plate 37 is adapted to bear. A ring-like gasket, not shown, of cork and rubber-like material may be interposed between the mating surfaces to seal the joint between` the plate 37 and the cylindrical section 34.

As best shown in Figure 1', a relatively thin gasket 38 f' 2,992,012 A F engages the outer surface of the boss 32 and the inwardly facing surface 39 of the end plate 37. A plurality of bolts 40 extending through the tabs 36, plate 37, and gasket 38 into engagement with threaded recesses formed in the cover 16 are used to attach the pump 24 to the engine and to assemble the parts of the pump casing 33 together.

A bearing 4l is carried by the end wall 35 and one end of a tubular shaft 42 is journalled therein. A pump rotor 43 is secured to the shaft 42 for rotation therewith and is positioned eccentrically with respect to the interior of the casing 33 as shown in Figures l, 5 and 6 whereby it bears against the inner surface `44 of the section 34 at one point such as 45.

The rotor 43 is provided with a pair of diametrically disposed, radial slots `46 in which a pair of pumping elements 47 are slidably mounted, pumping elements 47 are constantly urged radially outwardly of the rotor l43 by means of a coil spring 48 held under compression between them. lt will be appreciated from the foregoing that the extreme outer edges 49 of the pumping elements 47 slidingly engage the inner surface 44 of the cylindrical section 34. The wall 35 of the casing 33 is provided with a circumferentially extending slot 50 disposed on one side of the plane containing that point 45 and the rotational axis of the rotor 43. A similar slot 51 is formed in the plate 37 on the opposite side of the plane. The slot G, being on the suction side of the pump, serves as an air inlet and is in iluid communication with a pipe 52 leading from an air source (not shown). The slot 51 is in registration with aligned slots 53 and 54 provided in the gasket 38 and the cover 16, respectively. It will be appreciated from the foregoing that as the rotor 43 is rotated air is drawn into the casing 33 through the pipe 52 and slot 50 and delivered under pressure to the interior of the engine through slots 51, 53 and 54.

A coupling structure for driving the pump 24 from the cam shaft 13 is provided which includes a connecting member 55 having its end portions 56 hexagonal in shape. lIt is to be understood that the end portions could be square or rectangular in shape rather than hexagonal without departing from the spirit and scope of the invention. As stated hereinbefore, the shank portion 26 of the adapter element 27 is provided with external threads which are engageable with the threads formed in the recess 25. One end portion 56 of the connecting member 55 is received in the hexagonally shaped axially opening recess 30 in the enlarged portion 29 and the opposite end 56 is similarly received in a recess 57 formed in a socket member 58 suitably secured to the pump rotor 43. It will be appreciated that the coupling structure described above aifords a simple eh'icient means for drivingly interconnecting the engine cam shaft 13 and the pump 24.

As stated hereinbefore, the present invention contemplates the provision of means for supplying lubricating oil to the pump 24 from the pressure lubricating system of the engine in such a manner that the quantity received by the pump for lubricating the relatively movable parts thereof and for sealing the pressure side of the pump from the suction side is accurately controlled. The quantity of oil owing to the pump 24 is limited to an amount necessary to provide an adequate seal between the pressure discharge sides of the pump and to provide proper lubrication of the moving parts. By limiting the quantity of the oil flowing to the pump 24, over lubrication of the pump and its resulting adverse effects on the pumping capacity and efficiency to the pump is avoided. The means for supplying the pump 24 with lubricating oil and for controlling the supply includes an oil collecting, upwardly opening pocket 59 partially defined by an integrally formed U-shaped lip 6l) provided on the interior surface of the timing gear cover 16 above the axis of rotation of the pump 24 and to one side of a vertical plane containing the axis of rotation of the pump, as best illustrated in Figures 2 and 4. An upright sheet metal plate 61 is suitably secured to one end of the U- shaped lip 60 and serves as an end wall of the pocket 59. Integrally formed with and extending upwardly and transversely from the uppermost edges of the U-shaped lip portion 60 are flat ledges 62. From the foregoing it will be appreciated that a portion of the oil being discharged under pressure from the inclined passageway `20 to the upper part of the space enclosed by the detachable cover 16 and the end wall 10 of the engine block is deposited on the flat upper surfaces of the ledges 62. The oil deposited upon the uppermost surfaces of the ledges 62 drains by gravity to the pocket 59. The pocket 59 serves as a lubricantV reservoir for storing lubricant to be supplied to the pump 24.

As best shown in Figure 3, a duct 63 is provided in the timing gear cover 16 which extends axially from one bottom corner of the pocket 59. The opposite end of the duct 63 opens into one end of an elongated groove 64 formed in the outer surface or the surface engaging the gasket 38 of the timing gear cover 16. The groove 64 extends transversely and downwardly from the oil duct 63. The opposite terminal end of the groove 64 is in communication with an arcuately shaped groove 65 which is in axial alignment with a portion of the slot 50 provided in the wall 35 of the pump casing 33. The groove 65, in turn, is in communication with one end of a third groove 66 formed in the outwardly facing surface of the timing gear cover 16. The groove 66, as illustrated in Figure 4, extends upwardly and radially inwardly from the groove 65 and opens into the central opening 31 of the timing gear cover 16. It will be apparent that the surfaces defining the grooves 64, 65, and 66 of the timing gear cover 16 and the portion of the gasket 3S overlying the grooves define a lubricant passageway leading from the pocket 59 to one end of the pump rotor `47.

As shown in Figure 2, the gasket 38 is provided with a small aperture 67 which opens into the groove 65 adjacent the juncture point of the grooves 65 and 66 when the pump 24 and gasket 38 are assembled on the timing gear cover 16. The aperture 67 is in registration with one end of a relatively narrow groove 68 formed in the face of the end plate 37 of the pump 24 abutting the gasket 38. A small aperture 69 extends axially through the end plate of the pump 24 and establishes communication between the end of the slot 68 opposite the aperture 67 and the interior of the pump housing 33. It will be noted that the aperture 69 is in axial alignment with the inlet slot 50 which as pointed out hereinbefore is on the suction side of the pump 24. It will be appreciated therefore that the slot 68 and apertures 67 and 69 serve as a restricted passageway for establishing lubricant communication between the groove 65 and a point on the inner surface 44 which point is disposed on a suction side of the pump 24.

In operation lubricating oil delivered to the upwardly inclined passageway 20 from the engine pressure lubrieating system is discharged under pressure upon the timing gear 15 to lubricate the same. A portion of the oil will pass through the timing gear 15 and'be deposited upon the upper interior surface portion of the cover 16 and the end wall 10 of the engine. Also a certain amount of lubricant adhering to the timing gear 15 will be flung radially by centrifugal force upon the same upper interior surface portions. As the lubricant deposited upon the upper interior surface of the cover 16 drains downwardly by gravity a portion thereof flows transversely on the uppermost at surfaces of the-ledges 62 and is collected in the pocket 59. It will be appreciated that the ledges 62 serve as a means for directing lubricant to the pocket 59. The lubricant received in the pocket or lubricant reservoir 59 Vflows by gravity through the groove 64, 65 and 66 to the area in the Vicinity of the innermost end of the rotor 47. A certain amount of the oil owing from the groove 66 enters the pump 24 to lubricate the various moving parts of the pump. That portion of the lubricant owing from the groove 66 not entering the pump drains directly to the engine lubricating system sump, not shown in the bottom of the engine block. Inasmuch as the groove 66 extends upwardly from the groove 65 to the point where it opens into the central opening 31 and since the aperture 67 opens into the groove 65 adjacent the juncture of the ducts 65 and 66 the aperture 67 is vertically spaced below the point where the groove 66 opens into the central opening 31. Consequently even though insuicient oil is present in the grooves 64, 65 and 66 whereby the lubricant ows from the end of groove 66 into the opening 31 in the end plate 37 of the pump 24, the aperture 67 will be below the level of the lubricant within the groove 65. Thus by virtue of the fact that the interior of the pump 24 is in free lubricant communication with the lowermost point of groove 65 which point is below the outlet of groove 66, lubricant is available for lubricating the interior of the pump 24 even though only a small quantity of oil is present in the groove 65. Inasmuch as the groove 65 is in communication with the low pressure or the suction side of the pump 24 oil is drawn through the restricted slot 68 sealing the pressure side from the suction side and for lubricating the sliding engagement surfaces of the pump. It will be appreciated that since the depth of the groove 68 is relatively small and the width thereof when compared to its length is also small the cross-sectional area of the groove 68 is consequently small and tends to restrict theow of lubricant therethrough regardless of the pressure differential between the subatmospheric pressure developed by the pump and the pressure existing in the pocket 59 which is in fluid cornmunication with the groove 65. The oil received within the pump 24 is discharged with the air delivered to the interior engine groove slots 51, 53 and 54 provided in the pump and plate 37, gasket 38 and the timing gear cover 16 respectively.

From the foregoing it will be appreciated that after commencing operation of the engine after a few revolutions of the cam shaft 13, the pocket 59 will be sufficiently filled with oil to assure an adequate supply of lubricant for lubricating the interior of the pump 24 and the oil supply within the pocket 59 will be continuously re plenished by a portion of the oil deposited on the upper interior surface of the timing gear 16.

The embodiment of the invention chosen for the. purposes of illustration and description herein is not preferred for achieving the objects of the invention and developing the utility thereof in a most desirable manner due regard being had to existing factors of economy, simplicity of design and construction, production methods and improvementssought to be effected. It .will be appreciated therefore that the particular structural and functional aspects emphasized herein are not intended to exclude but rather to suggest such other adaptations and modications of the invention as fall within the spirit and scope of the invention as defined in the appended claims.

What is claimed is:

l. In an internal combustion engine having a pressuretype lubrication system and including a bearing adapted to receive lubricating oil under pressure from said lubricating system, a generally vertically disposed wall contiguous to said bearing provided with a circular opening in alignment with said bearing, said opening being encircled by an annular boss formed on the exterior surface of said wall, an engine driven shaft having one end journalled in said bearing, a pump including a cylindrical housing having an end wall mounted on said annular boss and a rotor having peripherally spaced pumping elements in sliding engagement with a portion of the inner surface of said housing, said pump housing end wall having a circular opening in alignment with the circular opening of said wall of said engine, said rotor being eccentrically journalled in said housing and having one end axially spaced from and in alignment with said shaft, and means for drivingly interconnecting said rotor and shaft; the combination including said wall of said engine and said end wall of said pump housing comprising means for supplying lubricating oil to said pump from said bearing to lubricate the sliding engagement surfaces of said pumping elements and said housing including a lubricant reservoir axially spaced between said pump and bearing and vertically spaced above the rotational axis of said shaft, lubricant passage means having one end opening into said circular opening in said engine Wall, and its opposite end in uid communication with said reservoir, means for impinging the interior surface of said engine wall vertically above said reservoir with lubricant under pressure from said bearing, means for guiding lubricant flowing vertically downwardly by gravity from said lubricant impinged surface to said reservoir, and a restricted passage means extending from said lubricant passage means to said sliding engagement surface of said pump housing.

2. The combination substantially as set forth in claim l, in which, said lubricant passage means is partially dened by a groove formed in the exterior face of said annular boss and a relatively thin gasket member disposed between said pump housing end wall and said annular boss, and said restricted passage is partially defined by a relatively narrow, elongated groove formed in the face of said pump housing end wall abutting said gasket member.

3. The combination substantially as set forth in claim 2, in which, said relatively narrow groove formed in said pump housing end wall is in axial alignment with a section of the groove formed on the exterior face of said annular boss, one end of said section tof said groove formed on the exterior face of said annular boss being vertically spaced below the point where said lubricant passage means opens into said circular opening of said engine wall, an aperture formed through said gasket member for establishing lubricant communication between one end of said relatively narrow groove formed in said pump housing end wall and said one end of said section of said groove formed on the exterior face of said annular boss disposed below the point where said groove opens into said circular opening formed through said annular boss.

4. In an internal combustion engine having a rotatable shaft journalled in a pressure lubricated bearing, a pump having a low pressure, suction side and a high pressure, discharge side, said pump including a rotor in axial alignment with said shaft and being drivingly connected thereto, the combination comprising, means for supplying lubricant to the low pressure, suction side of said pump from said bearing including a cover plate detachably secured to said engine having a vertical wall portion axially spaced from said bearing, said pump being mounted on the exterior of said vertical wall portion, a lubricant reservoir provided on the interior surface of said vertical wall portion above the axis of rotation of said shaft, lubricant passage means extending from said reservoir to the low pressure suction side of said pump including a restricted passage, said lubricant passage means being partially defined by an elongated groove formed in the exterior face of said vertical wall portion, lubricant transmission means for supplying a surface of said vertical wall portion vertically spaced above said reservoir with lubricant from said bearing, and means for directing lubricant from said surface of said vertical wall portion as it ows downwardly by gravity to said reservoir.

5. In an internal combustion engine having a rotatable shaft journalled in a pressure lubricated bearing, and a pump having a low pressure, suction side and a high pressure, discharge side, said pump including a housing having an'end wall and a rotor in axial alignment with said shaft and being drivingly connected thereto, the combination comprising, means for supplying lubricant to the low pressure, suction side of said pump from said bearing including a generally vertically disposed wall contiguous to said bearing, said pump housing end Wall being mounted on the exterior of said vertically disposed wall, a lubricant reservoir provided on the interior surface of said vertically disposed wall above the axis of rotation of said shaft, lubricant passage means extending from said reservoir to the low pressure, suction side of said pump including an elongated groove formed in the exterior face of said vertically disposed wall, means for impinging the interior surface of said vertically disposed wall above said reservoir with oil under pressure from said bearing, and means for guiding lubricant flowing downwardly by gravity from said lubricant-impinged surface of said vertically disposed wall to said reservoir.

6. In an internal combustion engine having a pressuretype lubricating system and including aV rotatable shaft, and a pump having a rotor in axial alignment with said shaft and being drivingly connected thereto, the combination comprising, means for supplying lubricant to said pump from said pressure-type lubricating system including a vertical wall axially spaced from one end of said shaft, said pump being mounted on the exterior of said vertical wall, a lubricant reservoir provided on the in, terior surface of said vertical wall above the axis of rotation of said shaft, lubricant passage means extending from said reservoir to the interior of said pump including an elongated groove formed in the exterior face of said vertical wall, and means for supplying said reservoir with lubricant from said pressure-type lubricating system.

7. In an internal combustion engine having a pressuretype lubricating system and a rotatable shaft, a pump axially spaced from one end of said shaft including a rotor in axial alignment and being drivingly connected thereto, the combination comprising, means for supplying lubricant to the interior of said pump from said pressure-type lubricating system including a vertical wall of said engine axially spaced from one of said shaft, said pump being mounted on the exterior of said vertical wall, a lubricant reservoir provided on the interior surface of said vertical wall above the axis of rotation of said shaft, lubricant passage means extending from said reservoir to the interior of said pump including an elongated groove formed in the exterior face of said vertical Wall, means for impinging the interior surface of said vertical wall vertically above said reservoir with lubricant under pressure from said pressure-type lubricating system, and means for guiding lubricant flowing vertically downwardly by gravity from said lubricant-impinged surface to said reservoir.

8. In an internal combustion engine having a pressuretype lubricating system and including a rotatable shaft, a pump having a rotor in axial alignment with said shaft and being drivingly connected thereto, the combination comprising, means for supplying lubricant to said pump from said pressure-type lubricating system including a vertical wall axially spaced from one end of said shaft, said pump being mounted on the exterior of said vertical wall, an open topped, substantially cup-shaped lubricant reservoir provided on the interior surface of said vertical wall above the axis of rotation of said shaft, lubricant passage means extending from said reservoir to the interior of said pump including an elongated groove formed in the exterior face of said vertical Wall, and means for supplying said reservoir with lubricant from said pressure type lubricating system.

9. in an internal combustion engine having a rotatable shaft journalled in a pressure lubricated bearing, and a pump having a rotor in axial alignment with said shaft and being drivingly connected thereto, the combination comprising, means for supplying lubricant to said pump from said bearing including a vertical Wall axially spaced from one end of said shaft, said pump being mounted on the exterior of said vertical Wall, an open-topped, s ubstgantiallyl cup-shaped lubricant reservoir provided on the interior surface of said vertical wall above the axis of rotation of said shaft, lubricant passage means extending from said reservoir to the interior of said pump including an elongated groove formed in the exterior face of said vertical wall,means for directing oil under pressure upwardly and axially from said bearing toward said vertical wall whereby a portion thereof impinges the interior surface area of said vertical wall above said reservoir, and means for directing lubricant impinged upon the interior surface area of said vertical Wall above said reservoir to said reservoir as it flows downwardly by gravity.

l0. The combination substantially as set forth in claim 9, in which, said lubricant reservoir is provided with a pair of axially extending, spaced vertical side walls, and s aid means for directing lubricant from s aid interior surface area of said vertical wall above said reservoir to said reservoir as it ilows downwardly by gravity includes a pair of axially projecting ledges having at upwardly facing surfaces, each of said ledges having one end merging into the top edge of a respective side wall of said reservoir and being inclined upwardly and transversely therefrom.

l1. In an internal combustion engine having a pressuretype lubricating system and including a rotatable shaft, a generally vertically dispod wall axially spaced from one end of said shaft, a pump including a housing having an end wall mounted on the exterior surface of said vertical wall and having a rotor in axial alignment with said shaft and being drivingly connected thereto, the combination including said vertical wall and said pump housing end wall comprising an open-topped, substantially cupshaped lubricant reservoir provided on the interior surface of said vertical wall above the axis of rotation of said shaft, means for supplying' said reservoir with lubricant from said pressure-type lubricating system, and lubricant passage means extending from said reservoir to the interior of said pump housing, said lubricant passage means being partially defined by a groove formed in the exterior face of said vertical wall and a relatively thin gasket member disposed between said pump housing end wall and said vertical wall, said lubricant passage means further including a restricted passage, said restricted passage being partially defined by a relatively narrow elongated groove formed in the face of said pump housing end wall abutting said gasket member.

12. In an internal combustion engine having a rotatable shaft journalled in a pressure lubricated bearing, a vertical wall axially spaced from one end of said shaft, and a pump having a housing and a rotor in axial alignment with said shaft and being drivingly connected thereto, an end wall of said pump housing being mounted on the exterior surface of said vertical wall, the combination including said pump housing end wall and said vertical wall comprising an open-topped, substantially cup-shaped lubricant reservoir provided on the interior surface of said vertical wall above the axis of rotation of said shaft, means for directing oil under pressure upwardly and axially from said bearing toward said vertical wall whereby a portion there: of impinges -the interior surface area of said vertical wall above said reservoir, means for directing lubricant impinged upon the interior surface area of said vertical wall above said reservoir to said reservoir as it flows downwardly by gravity, and lubricant passage means extending from said reservoir to the interior of said pump housing, said lubricant passage means being partially defined by a groove formed in the exterior face of said vertical wall and a relatively thin gasket member disposed between said pump housing end wall and said vertical wall, said lubricant passage means further including a restricted passage, said restricted passage being partially dened by a relatively narrow elongated groove formed in the face of said pump housing end Wall abutting said gasket member.

13. The combination substantially as set forth in claim 12, in which, said lubricant reservoir is provided with 'a pair of axially extending, spaced vertical side walls, and said means for directing lubricant from Vthe interior surface area of said vertical wall abofve 'said reservoir to said reservoir as it ows downwardly by gravity includes a pair of axially projecting ledges having at upwardly facing surfaces, each of Said ledges having one end merging into fthe top edge of Aa respective side wall of said reservoir and being inclined upwardly and transversely therefrom.

References Cited in the le of this patent UNITED STATES PATENTS Edwards Sept. 19, 1933 Warren Apr. 25, 1950 Alden Nov. 18, 1952 Orr Oct. 6, 1953 

